/*********************************************************************************
 *      Copyright:  (C) 2025 LingYun IoT System Studio
 *                  All rights reserved.
 *
 *       Filename:  named_socket_sever.c
 *    Description:  This file 
 *                 
 *        Version:  1.0.0(19/03/25)
 *         Author:  Guo Wenxue <guowenxue@gmail.com>
 *      ChangeLog:  1, Release initial version on "19/03/25 19:54:33"
 *                 
 ********************************************************************************/

#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/un.h>

#define SOCKET_PATH "/tmp/socket.domain"

int main(int argc, char **argv)
{
	int rv = -1;
	int listen_fd, client_fd = -1;
	struct sockaddr_un serv_addr; 
	struct sockaddr_un cli_addr;
	socklen_t cliaddr_len;
	char buf[1024];

	//listen_fd = socket(AF_UNIX, SOCK_STREAM, 0);
	listen_fd = socket(AF_LOCAL, SOCK_STREAM, 0);
	//创建套接字
	if(listen_fd < 0 )
	{
		printf("create socket failure: %s\n", strerror(errno));
		return -1;
	}
	printf("socket create fd[%d]\n", listen_fd);

	if( !access(SOCKET_PATH, F_OK) )
	{
		unlink(SOCKET_PATH);//删除已有套接字文件
	}

	memset(&serv_addr, 0, sizeof(serv_addr));
	serv_addr.sun_family=AF_UNIX;
	strncpy(serv_addr.sun_path, SOCKET_PATH, sizeof(serv_addr.sun_path)-1);
//绑定地址
	if( bind(listen_fd, (struct sockaddr *)&serv_addr, sizeof(serv_addr)) < 0 )
	{
		printf("create socket failure: %s\n", strerror(errno));
		unlink(SOCKET_PATH);
		return -2;
	}
	printf("socket[%d] bind on path \"%s\" ok\n", listen_fd, SOCKET_PATH);
//开始监听
	listen(listen_fd, 13);

	while(1) 
	{
		printf("\nStart waiting and accept new client connect...\n", listen_fd);
		client_fd = accept(listen_fd, (struct sockaddr*)&cli_addr, &cliaddr_len);
		if(client_fd < 0)
		{
			printf("accept new socket failure: %s\n", strerror(errno));
			return -2;
		}

		memset(buf, 0, sizeof(buf)); 
		if( (rv=read(client_fd, buf, sizeof(buf))) < 0)
		{
			printf("Read data from client socket[%d] failure: %s\n", client_fd, strerror(errno));
			close(client_fd);
			continue;
		}
		else if( rv == 0 )
		{
			printf("client socket[%d] disconnected\n", client_fd);
			close(client_fd);
			continue;
		}
		printf("read %d bytes data from client[%d] and echo it back: '%s'\n", rv, client_fd, buf);

		if( write(client_fd, buf, rv) < 0 )
		{
			printf("Write %d bytes data back to client[%d] failure: %s\n", rv, client_fd,
					strerror(errno));
			close(client_fd);
		}
		sleep(1);
		close(client_fd);
	}
	close(listen_fd);
}

